Automatic gas-analyzer.



"P.R.BOULTON.

AUTOMATIC GAS ANALYZER.

APPLICATION FILED APR.15, 191s.

Patented Nov. 4, 1913.

2 SHEETS-SHEET 1.

P. R. BOULTON.

AUTOMATIC GAS ANALYZER.

APPLICATION FILED APR. 15, 1913.

1,077,927. Patented Nov. 4, 1913.

2 SHEETS-SHEET 2.

nmrno srarns PATENT oar-ion rnnc var. n-AYMOND BOULTON, or BIRMINGHAM, ENGLAND.

r 1 AUTOMATIC GAS-ANALYZER,

To all whom it may concern;

Be I it known that I, Pnno vAn RAYMOND BOUL O a subject of the Kingdom of Great Britain, residing at The Electricity Works,

Summer Lane, Birmingham, in the county of War ick, Eng nd, have in d c tain Improvements in Automatic Gas-Analyzers, of which thefollo-wing is a specification. 1

This invention relates to improvements in apparatus for the automatic and continuous analysis, indication, and recording of gases, and has particular application to an improvediapparatus for indicating e'nd recording the percentage of carbon dio-xid in furnace fuel gases or the like, for the purpose of affording a simple and reliable indication of the efficiency of the firing and consequently of the efiective working of the boiler, L

While the aforesaid purpose is the primary object of this invention, I d9 not desire to limit the scope of its application, as with equal advantage it could be applied for indicating the percentage of gases other than carbon dioxid, with slight modifications to suit the other purposes to which it is to be appl ed! The present apparatus is of the type in which the gases to. be analyzed are brought into h vi ini y o a a orbent ap d. to absorb the ga or ga es to e e imated, and he cha acte istic eat r f my P t vention exists in the fact that it operates.

by virtue of the pressure created or varied as a result of the absorption. I

The apparatus according to; my presentinvention involves,-i'n combination, a pressure tank containing absorbent, a supply conduit for conveying to such pressure tank the gases to be analyzed, a conduit providng for t e egress f he gases from said pressure tank, means forcausing the gases t ter and leave said pressure tank, means for controlling the gases admitted to said pressure tank, means for controlling the gases eg-ressing from said pressure tank,

and means for continuously ascertaining, ins dicating, or recording the gases, said means operatingby virtue of the pressure. in said Pres re nk.

The n ture and c n tr t o o pparatus, operating by pressure and involv-. ing the at ire-recited combination, may Vary considerably, and while several modificai ns a e speci d he e nafter, th a e describ d by ay f examp e, as y ppa- Specification of Letters Ifatent.

ings, which diagrammatically illustrate'vwrious forms of my invention, and on Figure 1 is a diagram showing one general arrangement of my apparatus. Fig.

'2 repeats a part of the diagram shown in Fig. 1, but illustrates the alteration which occurs When an absorption of carbon dio-Xid has taken place. Fig. 8 repeats apart of the PatentedNom-el, 1913. Application filed April 15, 19213. Serial No. 761,277. I

diagram shown in Fig. 2, but illustrates the operation of the means of automatic compensation which may be provided to compensate for variations in the total pressure difi'erence. Fig. 4: illustrates an arrangement which may be employed in connection with the apparatus illustrated in Fig. 1, but in lieu of the compensating apparatus thereof. F ig, 5 illustrates in end sectional elevat-ion, a form of absorption tank which may be used in connection With the present invention, and by which liquid absorbent.

may be agitated during the operation of 'the apparatus. Fig, 6 illustrates in sectional elevation the absorption tank shown in g: 51 i Referring firstly to Figs. 1, 2, and 3,, two receptacles or cylinders a, b are provided,

conveniently of the same capacity, through which receptacles the gases to be analyzed successively pass, the gases entering the first receptacle (1: from the main source of supply, by a conduit f. After the gases have passed through the chamber a, and before they enter the chamber Z), they are caused to pass through an absorption tank 0 containing absorbent, an indicator or gage (hereinafter more fully referred to), being associated with said ressure tank. An ejecto:- or extractor e, of suitable type, is provided to produce a vacuum, or a pressure be low that of the atmosphere of any ,convenient' amount which will cause a how of the gases from the flue, chimney, or stack of the boiler or the like, the gases passing first through the pipe f into the receptacle a and then through a pipe 9 over the surface of the absorbent in the tank 0. The absorbent employed in the analysis of gases containing carbon dioxid may for instance be caustic potash solution, and the gases after the extraction of any carbon dioxid due to the passage throughthe absorbent tank pass through the pipe h to the second receptacle 1) and through the pipe 2' to the ejector 6. Connected with the receptacle a -is a valve or valves j which is arranged to alternately open the said receptacle to its inlet pipe 7 and to its discharge pipe g, and a similarly acting valve 7' is connected to the receptacle 6, the arrangement being such as to provide for an intermittent flow from the flue, to which is connected the pipe f, of the gases to be analyzed successively through the receptacle a, absorbent tank 0, and receptacle 6 to the ejector e. A gage or indicator (1 of the float and liquid type is arranged to indicate the difierence between the pressures between the receptacle a and the absorbent tank 0, and the absorbent tank 0 and the receptacle 6.

The method of operation may be expressed in the following manner. The receptacle or vessel (1 is alternately opened to the pipe 7 connected to the flue and to a pipe 9 connected to the absorption tank 0. The receptacle or vessel 6 is alternately connected to ,the tank 0 by, the pipe h and by the pipe i to an ejector or o ier suitable means 6 for producing a vacuum, or a pressure below that of the flue, thus inducing a flow of gases through thetank 0 containing a caustic potash or other absorbent solution. By means of suitable valves a cycle of operation is carried out as follows :1. The vessel or receptacle a is opened to the flue, the gases contained in vessel or receptacle a equal the pressure in the flue, and communication between a and the flue is cut ofl. 2. The vessel or receptacle bis openedto the ejector e and the gasescontained in b are reduced to the pressure produced by the ejector and communication between the receptacle 1) and the ejector is cut off. 3. Communicationbetween the vessels a, b andc is preferably simultaneously established when the pres; sure equalize, then communication is cut ofi Operations 1 and 2 preferably take place simultaneously. It will be seen therefore that gases are induced to flow throughthe tank 0 over the surface of the absorbent and provided no gas is absorbed, the pressure in v-the tank 0 will be equal to the mean between the mean of the pressures of the the pressure at the inlet from the flue and the pressure at the outlet to the ejector. If, however, a percentage of the gas passing into the tank cis absorbed, then the pressure in that tank willbe less than themean, and

gage, whereby any variation of the pressure of the gases due to absorption is 1nd1cated. When the diiference in pressure between the inlet. and the absorbent is equal to the pres-' sure between the absorbent and the outlet, the gage or indicator reads zero.

The gage to which reference has previously been made is adapted to measure the amountby which the pressure at the absorbent tank differs from the mean of the two extreme pressures expressed as a percentage of the difference between these two extreme pressures, and it comprises a float Z: of the inverted bell type having multiple chambers as shown, into which the pipes Z and o enter. The float 7a is mounted within a tank 3 in which there is a suitable amount of liquid neutral to the gases under analysis. A pipe m connects the upper part of the absorption tank 0 with the upper part of the tank y. Attached to the float k, which is influenced by the gases passing through the absorbent tank, is a system of linkage comprising a rod a t-pivoted at n to the float 7s, and pivoted at n to a bell-crank 0 hinged at 0 to a bracket on the tank 3 and pivotally connected at 0 to arod 12, the rod p being slidably connected to a slotted quadrant q hinged at 9 the quadrant having an indicating finger 1- thereon or connected therewith, said finger indicating against a suit-.

carbon dioxid) position of the linkage, and t Fig. 2 illustrates the position of the linkage when say 15% of carbon dioxid has been absorbed. In order to compensate for any variation of'pressure difference, between the gases before entering the receptacle a and' after leaving the receptacle b, and to allow of the indicator giving a correct reading, I provide a correction deviceconnected with the gage 03, comprising an additional float s and tank a; connected to the said float s is linkage which is connected to the aforesaid linkage, and is so arranged that should any angular movement of the slotted quadrant 9 take place, the indicator finger r is moved a proportionately greater or less distance over. the chart or index of the gage d, thus forming an automatic compensator for any variations of the total pressure difference. The linkage connected with the floats 8 comprises a rod t pivoted at t, and pivotally connected alt-t with the rod 72, reference to Fig- 3 of the drawings will illustrate by a gases and the gage finger 1' indicates zero,

a be more fully described: Assuming that the gases passing through the apparatus contain no carbon dioxid, then the amount of gasentering the apparatus is equal to the amount discharged therefrom, and consequently the pressure difference hereinbefore referred to, will be equal and the gage d n indicatczero. Assuming, however, that 'a' percentage of carbon dioxid, (say 15 is present, the indicator 1' ofthe gage Z will i take up a' different position, such position being. preferably expressed asa percentage. This position is seen in Fig. 2 of the accom panying diagrams.

In operation, the speed of the two valves 7' and connected to the receptacles a and b respectively, must hesynchroniz'edfthey may be combined in one valve, by placing the receptacles a and b adjacent to one another, or operatedfrom any convenient. source of power at a convenient speed, say two revolutions per minute, but such means of operation are not a feature of this invention. The indicating float 7c of the gage d may be in addition or alternatively arranged to operate a recording stylus contactingwith a revolving drum operated by clockwork orthe like, and from which a permanent record may be obtained. The arrangement shown in Fig. 4, which may be used in lieu of the compensating tank a in Fig. 1, comprises a tank 2 containing water or other suitable liquid and the upper .are obtained, or with the pipe 7 connecting part of whichtank above the surface of the water is in communication by a conduit 6 with the conduit z conn cting'the receptacle 7) with ejector e. A con5uit3 enters the tank' 2 passing to a positio suitably below the surface ,of the liquid therein, the said conduit 3 being in communication with the source from which the gases to be analyzed such source with the receptacle (1, so as to' permit of gases from the flue bubbling through the liquid in the tank 2. By the use of the apparatus shown iniFig. 4, the difference of pressure in the pipes" f, z', is maintained constant and it is thusi unnecessary to provide an apparatus such as 2 adapted to compensate for changes in the pressure difference. The pressure difference maintained by means of the tank 2 is determined by the head ofliquid in such tank,- and it will be obvious that this head must be I absorbent.

ing. the members 31 are intermittently submaintained constant, thereby determining and maintaining the vacuum produced by the ejector; that is the pressure of gas in the tank 2 is less than the pressure in the flue by a constant amount.

In the arrangement shown in Fig. 1, either in cases in which the compensating element a is employed or in which the apparatus shown in Fig. 4 is employed, 1 advantageously provide a valve m in the conduit m, the said valvebeing so operated as to close or isolate the pressure tank 0 except throughoutv the time during which it is in communication with. the other tanks.

The special form ,of absorbent tank shown in Figs. .5. and 6 which may beused in connection with the present invention, is comprised of a cylindrical tank 29 arranged on a horizontal axis and mounted to be oscillated on such axis advantageously automatically. The said tank 29 is furnished internally .witha perforated partition. 30 adapted to carry members 31 of'any suitableform adapted to offer a large surface to the liquid By. the oscillations pf the easmergedand extracted from the liquid ab sorbent, the arrangement being such that while the articles 31 on one side of the casing are submerged, articles 31 v on the other side of the casing are raised above the surface of the liquid .after being freshly coated. The conduits 32 offering communication with the interior of the casing 29, to and from which conduits 32 the gas is conyeyed through the medium-of flexible con- .duit connections, are each bifurcated or branched into two conduits 33 which communicate with the casing at different points in" its circumference, in such a. manner that when .the casing aperture pertaining to one' conduit 33 is submerged, the casin aper ture pertaining to the pther conduit 33 is elevated above the surface of the liquid,

thus offering a free passage for theggases under any casing 29.

What Iclaim as my invention and desire to secure by Letters Patent is 1. Apparatus for the analysis of gases, havin 'n combination, an absorption tank cont ning an absorbent, a supply conduit for conveying to said tank the gases tobe analyzed, an ingress receptacle associated with suchsupply conduit, and through which the gases are adapted to pass before arriving at the absorption tank, an-egress conduit providing for the egress of the gases from said absorption tank, a receptacle ascircumstance of movement of the sociated with said egress conduit, and

throu h 'whichthe gases are adapted to passv after caving the pressure tankfmeans for causing thegases to successively traverse the ingress receptacle, the pressure tank, and

the egress receptacle, means for controlling the passage of the gases to and from the ingress receptacle, means for controlling the passage of the gases to and from the egress receptacle such last-mentioned means being adapted to operate in appropriate relationship with the controlling means pertaining to the ingress receptacle, and means for determining the percentage of gas constituent absorbed, said means being adapted to compensate for the variations in pressure in the gas before entering the ingress receptacle and after leaving the egress receptacle.

2. Apparatus for the analysis of gases,-

having, in combination, an absorption tank containing absorbent, a supply conduit for conveying to said tank the gases to be analyzed, an ingress receptacle associated with such supply conduit, and through which the gases are adapted to pass before arriving [at the absorption tank, an egress conduit I gress receptacle, means for controlling the passage of the gases to and from the egress receptacle, such last-mentioned means being adapted to operate in appropriate relationship with the controlling means pertaining tot-he ingress receptacle, means for maintaining constant the difference of pressure between the gases before entering the ingress receptacle, and the gases after leaving theegre'ss receptacle, and means for determining the percentage of as constituent absorbed, said means being adapted .to compensate for the variations in pressure in the gas before entering the. ingress receptacle and after leaving the egress receptacle. v

3. A gas analyzing apparatus comprising in combination, an absorption tank containing an absorbent substance, means for flowing gas through said tank, and pressure responsive mechanism connected to said tank and adapted in conjunction with said tank, to determine the percentage of gas constituent absorbed, said mechanism being adapted to compensate for the variations in pressure in the gas before entering the apparatus.

In witness whereof I have hereunto set my hand in the presence of two Witnesses.

PERCIVAL RAYMOND BOULTON. Witnesses ARTHUR BROWN, ARCHIBALD LAMB. 

